The web of private coin collectors increased dramatically during the 19th century, and handbooks for the novice began to appear. The scope of collecting broadened from ancient coins to coins of the world, and the activity became a popular hobby. Numismatic societies were formed throughout Britain, Europe, and the United States, with membership open to all ranks of the general public. Periodicals about coin collecting emerged, and the growing appetite of new advocates led to a prosperous industry.

The 20th century saw an even greater widening of the coin-collecting fraternity, with the establishment of coin shows, numismatic conventions, international conferences, academic symposia, and a proliferation of local clubs. Some of these clubs banded together to form large and influential associations. At the same time, the community of professional numismatists (coin dealers) became more tightly knit, and trade associations were established.